scholarly journals Recovery of Lignosulfonates from Spent Sulfite Liquor Using Ceramic Hollow-Fiber Membranes

Membranes ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 45 ◽  
Author(s):  
Daniel Humpert ◽  
Mehrdad Ebrahimi ◽  
Annika Stroh ◽  
Peter Czermak
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Raw Material ◽  
Hollow Fiber Membranes ◽  
Permeate Flux ◽  
Fiber Membranes ◽  
Wall Shear ◽  
Spent Sulfite Liquor

Spent sulfite liquor is an abundant but currently less used wastewater stream from the pulp and paper industry. The recovery of lignin from this resource would provide an inexpensive raw material for the manufacture of fuels and fine chemicals. Here we investigated the suitability of ceramic hollow-fiber membranes for the concentration of spent sulfite liquor as an alternative to common membrane technologies. We tested three ceramic hollow-fiber membranes (3, 8, and 30 nm) in different membrane processes (fed-batch and total recycle mode) and compared their performance with the widely-used tubular membrane geometry. We also evaluated backflushing as a strategy to reduce membrane fouling during filtration. The juxtaposition of the two membrane geometries revealed that wall shear stress is the most important process parameter for the assessment of membrane performance according to permeate flux. The higher the wall shear stress, the higher the permeate flux. Due to the smaller inner diameter of the hollow-fiber membranes, higher wall shear stress can be achieved more easily. Backflushing had no effect on the permeate flux during the concentration experiments.

Development of a Polymeric Carbon Nanocomposite Hollow-Fiber Membrane for Wastewater Treatment

2021 ◽  
Vol 21 (7) ◽  
pp. 3711-3715
Author(s):  
Jeongdong Choi ◽  
Eun-Sik Kim
Keyword(s):  
Carbon Nanotubes ◽  
Graphene Oxide ◽  
Hollow Fiber ◽  
Hollow Fiber Membranes ◽  
Permeate Flux ◽  
Fiber Membranes ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Polymeric Carbon ◽  
Carbon Nanocomposite

This study investigated experimental parameters to fabricate polymeric carbon nanocomposite hollow-fiber membranes with graphene oxide and multi-walled carbon nanotubes. This case was different from that of flat-sheet type membranes in that the characteristics of the hollow-fiber type membranes were affected by the structure of the spinneret, the flow rate of the injected polymer and draw solution, and the mixing ratio. The membranes were characterized in terms of mechanical strength, porosity, hydrophilicity, and permeate flux using different solutions. The results reveal a mechanical strength of the carbon nanocomposite hollow-fiber membranes that is about 47.8% higher than that of hollow-fiber membranes without carbon nanomaterials. The porosity and surface hydrophilicity changed to produce more applicable membranes for water and wastewater treatment. As for the permeate flux, the nanocomposite membrane with graphene oxide showed a higher flux compared to the multi-walled carbon nanotubes membrane, which could be influenced by structural effects of the carbon materials.

Performance and antifouling enhancement of polyethersulfone hollow fiber membranes incorporated with highly hydrophilic hydroxyapatite nanoparticles

RSC Advances ◽  
2016 ◽  
Vol 6 (50) ◽  
pp. 44480-44488 ◽  
Author(s):  
Esmaeil Salimi ◽  
Azadeh Ghaee ◽  
Ahmad Fauzi Ismail
Keyword(s):  
Water Purification ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Hollow Fiber Membranes ◽  
Hydroxyapatite Nanoparticles ◽  
Fiber Membranes

Membrane fouling is one of the main drawbacks in water purification applications. The present work indicated that the fabricated HAp/PES hollow fiber membranes presented better hydrophilicity, permeation and anti-fouling performance compared to PES membranes.

scholarly journals The Effect of Membrane Material and Surface Pore Size on the Fouling Properties of Submerged Membranes

2016 ◽  
Author(s):  
Sungil Jeon ◽  
Saeid Rajabzadeh ◽  
Ryo Okamura ◽  
Toru Ishigami ◽  
Susumu Hasegawa ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Pore Size ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Polymeric Membrane ◽  
Transmembrane Pressure ◽  
Hollow Fiber Membranes ◽  
Membrane Material ◽  
Pore Sizes ◽  
Fiber Membranes

We aimed to investigate the relationship between membrane material and development of membrane fouling in a membrane bioreactor (MBR) using membranes with different pore sizes and hydrophilicities. Batch filtration tests were performed using submerged single hollow fiber membrane ultrafiltration (UF) modules with different polymeric membrane materials including cellulose acetate (CA), polyethersulfone (PES), and polyvinylidene fluoride (PVDF) with activated sludge taken from a municipal wastewater treatment plant. The three UF hollow fiber membranes were prepared by a non-solvent-induced phase separation method and had similar water permeabilities and pore sizes. The results revealed that transmembrane pressure (TMP) increased more sharply for the hydrophobic PVDF membrane than for the hydrophilic CA membrane in batch filtration tests, even when membranes with similar permeabilities and pore sizes were used. PVDF hollow fiber membranes with smaller pores had greater fouling propensity than those with larger pores. In contrast, CA hollow fiber membranes showed good mitigation of membrane fouling regardless of pore size. The results obtained in this study suggest that the surface hydrophilicity and pore size of UF membranes clearly affect the fouling properties in MBR operation when using activated sludge.

Membrane fouling properties of hollow fiber membranes prepared from cellulose acetate derivatives

2011 ◽  
Vol 376 (1-2) ◽  
pp. 102-109 ◽  
Author(s):  
Takashi Shibutani ◽  
Toshihiko Kitaura ◽  
Yoshikage Ohmukai ◽  
Tatsuo Maruyama ◽  
Shuji Nakatsuka ◽  
...  
Keyword(s):  
Cellulose Acetate ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Hollow Fiber Membranes ◽  
Fiber Membranes

scholarly journals Seawater Desalination by Modified Membrane Distillation: Effect of Hydrophilic Surface Modifying Macromolecules Addition into PVDF Hollow Fiber Membrane

Membranes ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 924
Author(s):  
Mochammad Purwanto ◽  
Nindita Cahya Kusuma ◽  
Ma’rup Ali Sudrajat ◽  
Juhana Jaafar ◽  
Atikah Mohd Nasir ◽  
...  
Keyword(s):  
Hollow Fiber ◽  
Polyvinylidene Fluoride ◽  
Hollow Fiber Membrane ◽  
Membrane Distillation ◽  
Hydrophilic Surface ◽  
Hollow Fiber Membranes ◽  
Permeate Flux ◽  
Seawater Desalination ◽  
Salt Rejection ◽  
Fiber Membranes

Hollow fiber membranes of polyvinylidene fluoride (PVDF) were prepared by incorporating varying concentrations of hydrophilic surface-modifying macromolecules (LSMM) and a constant amount of polyethylene glycol (PEG) additives. The membranes were fabricated by the dry-wet spinning technique. The prepared hollow fiber membranes were dip-coated by hydrophobic surface-modifying macromolecules (BSMM) as the final step fabrication. The additives combination is aimed to produce hollow fiber membranes with high flux permeation and high salt rejection in the matter of seawater desalination application. This study prepares hollow fiber membranes from the formulation of 18 wt. % of PVDF mixed with 5 wt. % of PEG and 3, 4, and 5 wt. % of LSMM. The membranes are then dip-coated with 1 wt. % of BSMM. The effect of LSMM loading on hydrophobicity, morphology, average pore size, surface porosity, and membrane performance is investigated. Coating modification on LSMM membranes showed an increase in contact angle up to 57% of pure, unmodified PVDF/PEG membranes, which made the fabricated membranes at least passable when hydrophobicity was considered as one main characteristic. Furthermore, The PVDF/PEG/4LSMM-BSMM membrane exhibits 161 °C of melting point as characterized by the DSC. This value indicates an improvement of thermal behavior shows so as the fabricated membranes are desirable for membrane distillation operation conditions range. Based on the results, it can be concluded that PVDF/PEG membranes with the use of LSMM and BSMM combination could enhance the permeate flux up to 81.32 kg·m−2·h−1 at the maximum, with stable salt rejection around 99.9%, and these are found to be potential for seawater desalination application.

scholarly journals Effect of Concentric Annular Gap Flow on Wall Shear Stress of Stationary Cylinder Pipe Vehicle under Different Reynolds Numbers

2020 ◽  
Vol 2020 ◽  
pp. 1-19 ◽  
Author(s):  
Xiaomeng Jia ◽  
Xihuan Sun ◽  
Jiaorong Song
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Reynolds Numbers ◽  
Industrial Applications ◽  
Raw Material ◽  
Theoretical System ◽  
Annular Gap ◽  
Gap Flow ◽  
Wall Shear ◽  
Motion Characteristics

The tube-contained raw material pipeline hydraulic transportation technology is an optimization and improvement of traditional hydraulic capsule pipeline (HCP) transport. It has the advantages of lower resource consumption, environmental protection, and less demand for human resources and has the ability to directly transport solids, liquids, and gases. The cylinder pipe vehicle is the core component of tube-contained raw material pipeline hydraulic transportation; its motion characteristics and energy consumption are affected by wall shear stress. When the cylinder pipe vehicle is stationary, the annular gap flow will affect the wall shear stress. This paper studies the wall shear stress and annular flow field distribution of a stationary cylinder pipe vehicle under different Reynolds numbers. The results show that as the Reynolds number increases, both the wall shear stress and the annular gap flow velocity show a gradually increasing trend. The wall shear stress and the velocity of the annular gap flow show some correlation, but there are differences in the trend of axial and circumferential wall shear stress along the length of the cylinder pipe vehicle. The research in this article will further improve the theoretical system of hydraulic conveyance of barrel-loading pipelines and provide a theoretical basis for the realization of industrial applications as soon as possible.

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